Advances in the diagnosis and treatment of dry eye.

The core mechanism of dry eye is the tear film instability. Tear film-oriented diagnosis (TFOD) is a concept to clarify the cause of tear film instability by tear film, and tear film-oriented treatment (TFOT) is a concept to treat dry eye disease by replacing the lacking components of the tear film layer based on the TFOD. In TFOD, the fluorescein breakup pattern of the tear film is important, and the subtype of dry eye can be judged to some extent from the breakup patterns. Current noninvasive devices related to the dynamic analysis of the tear film and visual acuity enabled the diagnosis of dry eye, subtype analysis, and the extent of severity. In Asian countries, secretagogues represent the main treatment in TFOT. Since meibomian gland dysfunction is a factor that greatly affects the tear breakup time, its treatment is also essential in the dry eye treatment strategy. A newly discovered dry eye subtype is the short breakup time-type (BUT) of dry eye. The only abnormal finding in this disease is the short BUT, suggesting a relationship with ocular neuropathic pain and eye strain. Recently, data from many studies have accumulated which show that dry eye is a life-style disease. In addition to the treatment of dry eyes, it is becoming possible to prevent the onset by intervening with the daily habits, diet, exercise and sleep, etc. It has been pointed out that oxidative stress is also involved in the pathology of dry eye, and intervention is being carried out by improving diet and taking supplements. Future research will be needed to link clinical findings to the molecular biological findings in the tear film.
Competing Interests: Declarations of competing interest Takashi Kojima reports personal fees from Staar Surgical, Santen Pharmaceutical Co., Ltd., Johnson & Johnson, Otsuka Pharmaceutical Co., Ltd., Carl Zeiss Meditec, Echo Electricity Co., Ltd., and Alcon Japan, outside the submitted work. Murat Dogru reports personal fees from Santen Pharmaceutical Co., Ltd, Otsuka Pharmaceutical Co., Ltd, and Echo Electricity Co., Ltd., and, outside the scope of the paper, receives research grants from Echo Electrical Co., Kobayashi Pharma and I.com, Inc. Kazuo Tsubota reports consultancies and research funding received from Santen Pharmaceutical Co., Ltd., Wakamoto Pharmaceutical Co., Ltd, and Otsuka Pharmaceutical Co., Ltd.; research funding received from Kowa Company; patent holder for the method and the apparatus used for the measurement of functional visual acuity (US patent no: 255 7470026), inventor of JINS Moisture eye glasses by JINS, Inc., patent holder; and outside the submitted work, he reports the position of CEO of Tsubota Laboratory, Inc. a company in the dry eye field; consultancies for Laboratoires Thea and Novaliq GmbH; investor in Tear Solutions and Tissue Tech, Inc.; research funding from Rohto Pharmaceutical Co., Ltd., Pfizer, R-Tech Ueno, Ophtecs, Alcon Japan, and AMO Japan K.K. Motoko Kawashima and Shigeru Nakamura report no financial interests.
(Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.)